Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX: 799

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-799 A Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-799 0 Chicago Zone 01-Superior IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2005-04-15   
312-799 1 Chicago Zone 01-Superior IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2005-01-04   
312-799 2 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-799 3 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-799 4 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-799 5 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358      
312-799 6 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2000-07-28   
312-799 7 Chicago Zone 01-Superior IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2000-08-29   
312-799 8 Chicago Zone 01-Superior IL CHCGILSUDS2  9329 ILLINOIS BELL TEL CO 358   2000-11-18   
312-799 9 Chicago Zone 01-Superior IL CHCGILMF6MD  6529 T-MOBILE USA, INC. 358   2005-01-04   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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